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81.
Experimental results for the thermal conductivity of ammonia, propane, butane, isobutane, and propylene are reviewed, with special attention given to the liquid phase. New equations for the thermal conductivity of these five substances applicable for practical use over wide ranges of temperature and pressure including the critical region are proposed based on the experimental data. The present equations as well as the existing equations are compared with the experimental data. Compared with existing equations for ammonia, isobutane, and propylene, which are not reliable in the liquid phase, the behavior of the thermal conductivity for these substances is much improved using the present equations.  相似文献   
82.
The rate of iodine absorption by granular starch suspended in KI solution is examined. The rate controlling step is found to be the intraparticle diffusion of iodine. The process agrees well with a core-shrinking model. The apparent diffusivity of iodine in granular starch is determined to be (6.8 ± 0.5) × 10−8 cm2/sec at 25°C.  相似文献   
83.
A framework for damage mechanics of concrete is applied to simulate the nonlinear elastic deformation behavior of concrete using finite element method (FEM). A rather simple isotropic damage model containing essentially no adjustable parameters is shown to produce results in remarkably good agreement with sample experimental data: the damage law requires only the fracture energy to be defined completely. The model is achieved by introducing a damage surface that is similar to the yield function in the conventional theory of plasticity. A special form of damage surfaces is constructed to illustrate the application of the model. A new damage criterion, defined as an equivalent strain norm, is proposed, in order to take into consideration the asymmetric behavior of concrete. For verifying the FEM program including the model, deformations predicted by this model are compared with both the experimental ones for the concrete structural model and the ones calculated without application of the continuum damage mechanics.__________Translated from Problemy Prochnosti, No. 3, pp. 57 – 74, May – June, 2005.  相似文献   
84.
Abstract

Co-stabilised (Y,Mg) partially stabilised zirconia (PSZ) ceramics with MgAl2O4 spinel additions were produced, with industrial zirconia as the main starting material. Powders were prepared using a mechanical milling–mixing process. The effect of the annealing process on the mechanical properties, phase compositions, and microstructure of fine grained PSZ ceramics was investigated.  相似文献   
85.
A polyanhydride implant containing gentamicin sulfate was fabricated using a laboratory-scale injection-molding machine. After injection molding, the implants were subject to heat treatment at 60°C for various time periods with or without nitrogen protection. The impact of this heat treatment on the in vitro properties of the implants including copolymer molecular weights, mechanical properties, and in vitro drug-release profiles was investigated. This heat treatment caused a drastic drop in the molecular weight of the copolymer. Heating without nitrogen protection resulted in the hardening of the implant, but heating in the presence of nitrogen rendered the implant less rigid. It was also found that a faster in vitro drug release profile was shown by implants heated without nitrogen protection and a pronounced slowing down in drug release was exhibited by implants heated with nitrogen protection.  相似文献   
86.
We have developed a CCD calibration system using fluorescent X-ray lines with energies ranging from 1.49 keV (Al K) to 11.2 keV (Se K). The absolute X-ray flux is calibrated by a gas proportional counter, while the emerging spectra are monitored by solid-state silicon detectors. In order to suppress contaminating X-rays in the fluorescence spectra, mechanical collimators were set in the X-ray beam line, high-purity targets for fluorescent lines were used, and band-pass filters were put on the X-ray beam line. As for the purity of the fluorescent X-rays, the typical purity achieved was 98%.  相似文献   
87.
In this paper we present the results of AC loss measurements on silver clad monocore tapes of Tl-1223 prepared by the powder-in-tube method. Losses arising from an external AC magnetic field are compared with those generated by AC transport currents (self-field losses). Critical current densities are derived from magnetic loss data and compared with those measured by the four point transport method. It was found that mechanically induced stresses (introduced by bending) only have a significant effect on the transport losses, via the critical current degradation. Such changes are not seen in measured magnetic losses, which are independent of mechanical stress, and remain unchanged, at least in the stress range used in our experiment.  相似文献   
88.
89.
Co-culture system, in which two or more distinct cell types are cultured together, is advantageous in that it can mimic the environment of the in vivo niche of the cells. In this study, we presented a strategy to analyze the secretome of a specific cell type under the co-culture condition in serum-supplemented media. For the cell-specific secretome analysis, we expressed the mouse mutant methionyl-tRNA synthetase for the incorporation of the non-canonical amino acid, azidonorleucine into the newly synthesized proteins in cells of which the secretome is targeted. The azidonorleucine-tagged secretome could be enriched, based on click chemistry, and distinguished from any other contaminating proteins, either from the cell culture media or the other cells co-cultured with the cells of interest. In order to have more reliable true-positive identifications of cell-specific secretory bodies, we established criteria to exclude any identified human peptide matched to bovine proteins. As a result, we identified a maximum of 719 secreted proteins in the secretome analysis under this co-culture condition. Last, we applied this platform to profile the secretome of mesenchymal stem cells and predicted its therapeutic potential on osteoarthritis based on secretome analysis.  相似文献   
90.
The effectiveness of manual therapy in reducing the catabolic effects of performing repetitive intensive force tasks on bones has not been reported. We examined if manual therapy could reduce radial bone microstructural declines in adult female Sprague–Dawley rats performing a 12-week high-repetition and high-force task, with or without simultaneous manual therapy to forelimbs. Additional rats were provided 6 weeks of rest after task cessation, with or without manual therapy. The control rats were untreated or received manual therapy for 12 weeks. The untreated TASK rats showed increased catabolic indices in the radius (decreased trabecular bone volume and numbers, increased osteoclasts in these trabeculae, and mid-diaphyseal cortical bone thinning) and increased serum CTX-1, TNF-α, and muscle macrophages. In contrast, the TASK rats receiving manual therapy showed increased radial bone anabolism (increased trabecular bone volume and osteoblast numbers, decreased osteoclast numbers, and increased mid-diaphyseal total area and periosteal perimeter) and increased serum TNF-α and muscle macrophages. Rest, with or without manual therapy, improved the trabecular thickness and mid-diaphyseal cortical bone attributes but not the mineral density. Thus, preventive manual therapy reduced the net radial bone catabolism by increasing osteogenesis, while rest, with or without manual therapy, was less effective.  相似文献   
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